Amygdala and Hypothalamus: Historical Overview With Focus on Aggression

Abstract

Aggressiveness has a high prevalence in psychiatric patients and is a major health problem. Two brain areas involved in the neural network of aggressive behavior are the amygdala and the hypothalamus. While pharmacological treatments are effective in most patients, some do not properly respond to conventional therapies and are considered medically refractory. In this population, surgical procedures (ie, stereotactic lesions and deep brain stimulation) have been performed in an attempt to improve symptomatology and quality of life. Clinical results obtained after surgery are difficult to interpret, and the mechanisms responsible for postoperative reductions in aggressive behavior are unknown. We review the rationale and neurobiological characteristics that may help to explain why functional neurosurgery has been proposed to control aggressive behavior.

Perceptual Behavior Depends Differently on Pupil-Linked Arousal and Heartbeat Dynamics-Linked Arousal in Rats Performing Tactile Discrimination Tasks

“…The hypothalamus projects to the spinal cord structures and brain stem to regulate the sympathetic and parasympathetic tones through medial forebrain bundle and the dorsal longitudinal fasciculus. The hypothalamus forms heavy connections with brain structures mediating emotional responses to affective or aversive stimuli, including amygdala and prefrontal cortex (Saper, 2000 ; Phan et al, 2003 ; Gouveia et al, 2019 ). Consequently, heartbeat dynamics has long been utilized as an indicator of stress (Kim et al, 2018 ).…”

International Legal Approaches to Neurosurgery for Psychiatric Disorders

“…For example, self-injurious and aggressive behavior co-occurs sometimes with cognitive disability in some conditions (Arron et al, 2011 ). DBS and ablative NPD are being actively explored to address these aggressive behavioral issues (Gouveia et al, 2019 ). Research into forms of NPD that are prohibited legally in some places may instead proceed in countries with less restrictive legal environments, although those countries may have alternative forms of oversight that are adequate (e.g., strong research ethics systems and good checks and balances in the surrogate consent rules).…”

Sex vs Gender: Are We there Yet? A Biological Location for Gender, not Sex.

“…The components of the neural network that regulate aggressive behavior include the amygdala, the hypothalamus, and the orbitofrontal cortex (Gouveia et al, 2019;Unger et al, 2015), all of which are noted as being sexually differential. Testosterone plays a significant role in the arousal of these behavioral manifestations in the brain centers involved in aggression and on to the development of the muscular system that enables their realization.…”

“…Aggressive behavior is a primitive social conduct typical of ancient Anthropocenes that was essential for individuals to compete for food, territory, and mating (Gouveia et al, 2019). Males of the modern Anthropocene are still more likely to exhibit higher levels of visuospatial and navigational skills, as well as direct aggression (Kopsida et al, 2009).…”